Hi, I think it would be more useful to categorize the tools, and differentiate between self-learning and more pedagogic, classroom-like eLearning, as these are significantly different.

Also, you mention for example Firefox and Opera as two separate tools for eLearning, when they are essentially the same thing: web browser. The only difference is preference of browsers (aside from a technical standpoint or extensibility, like Firefox supported plugins, but because of their exclusivity they should be mentioned separately).

The list could be made more effective through categorization of the tools, with categories such as social networking (Facebook, e-mail applications, etc.), social bookmarking (stumbleupon, delicious), content management (drupal, etc), and so on, see which category is the most used, then break each category down into the most popular applications.

Don't get me wrong, the list is great and it serves as a great starting point, but a lot more could me gotten out of the information if it is presented with more depth and analysis.

I like that you've included a lot of free resources, it just goes to show that anyone can produce great training regardless of the budget if they get a little creative. Clients of mine are always a little cautious when I tell them their LMS can cost $0 or $300,000, just depends on what they want,
-Eric B.